The invention concerns a standard stuffed food speciality product, a method for producing this product, and a device implementing this method.
There already exist food co-extrusion methods, as well as single extrusion systems, food or non-food being almost similar to co-extrusion via their design.
There is for example a system used in particular in the confectioner trade Known by an expert in this field under the name xe2x80x9cRHEONxe2x80x9d including an integrated device made up of Two wing pumps and their hoppers meeting together at the level of a standard coextrusion head. The casing of the product is formed at the same time as the stuffing in an extremely short die (2 to 3 cm). No cooking is possible in the device which supports excessively hot raw material with difficulty, typically above 60xc2x0 C. This system is complex to mount and dismantle involving at least thirty mechanical elements and is extremely difficult to clean when cheese is used. This system is in particular used to coextrude large shapes, stuffed balls, stuffed rolls, large diameter sticks (minimum diameter 20 mm) or gnocchi.
With cheese in particular, small cheese sticks with a diameter of between 10 and 15 mm, indeed less, cannot be made without significantly modifying the device. The cost and low capacity of the machine are negative elements for economically producing small items, such as sticks or similar stuffed cheese moulds.
There is also a method similar to the preceding one commonly known as xe2x80x9cVEMAGxe2x80x9d, the difference being that the device is not integrated in a given device. In fact, it concerns two thrustors conjugated with a coextrusion head. This head is extremely short and generally remains with a diameter of more than 20 mm so as to obtain a product at reasonable production costs.
In all these cases, the cost of the system would be prohibitive for small items, such as food sticks, especially stuffed or cheese sticks.
There is also an injection filling method. In fact, there are products which combine brioche type coextruded products which are stuffed after cooking using an injection needle. This system does not in general applies to cheeses.
There are also stuffed type products which may resemble coextruded products. For example, by starting with a product rolled from a strip 2 to 3 mm thick with a width of 10 cm, this product is obtained by placing a stuffing at the centre of the strip before rolling. This is the case for example with bread containing chocolate. This method could be applied to cheese under certain formulation conditions: in particular the glueing and joinability properties of the cheese pastry. The product yield is extremely different from a stuffed cheese specialty to be described subsequently.
There are also co-pushing systems or other thrustor systems for co-pushing sausages. The result appears for example in the form of sausages with a cheese heart.
It is difficult to have the system adapt to high dry extract cheeses described in the remainder of the text.
The invention seeks to obtain stuffed food specialities, especially cheese ones, which are typically small with a lower diameter of less than 20 mm and in particular between 10 and 15 mm, thus mitigating the drawbacks of the prior art so as to obtain this type of product.
The invention also seeks to obtain these products by using cheese pastries having a high dry extract reaching of between 50 and 60%. With the coextrusion systems of the prior art, the shearing forces in the coextrusion die are too high to obtain a good product yield.
The invention also seeks to use a possible wide variety of formulations for the production of the desired products.
According to a first characteristic, the invention concerns a method for producing a food product including a solid casing coating at least one stuffing from a food bass used to form the casing of the product and at least a food stuffing material in a coextrusion device including a coextrusion die fed with the food base and the stuffing material(s), the method including the following successive stages:
formation in a first section of the die of the casing which solidifies via a thermic effect, this first section being longitudinally traversed by at least one transfer hollow needle of the stuffing, one hollow needle per stuffing material penetrating into a second section of the die, the start of the second section being defined by the outgoing extremity of the shorter hollow needle;
a stuffing in the second section of the die of the solid casing formed in the first section of the die with the stuffing material(s) coming out of the hollow needles traversing the first section;
recovery of the product including the external casing filled with the stuffing material(s) at the die outlet.
The food base is typically proteinic and can be a polysaccharide.
According to a first embodiment, the casing is formed in the first section of the die by cooling, normally via the circulation of water or another similar fluid.
According to one variant, natural cheeses, fresh curds or non-molten cheese specialities are used for the casing material.
According to another variant, molten cheeses or molten cheese specialities with or without melting salts are used for the casing material.
According to one embodiment, the method includes the following stages:
preparation of the stuffing and casing at a temperature of about 90xc2x0 C. in the feed hoppers;
cooling at a temperature close to 80xc2x0 C. of the stuffing and cooling at a temperature of about 60xc2x0 C. of the casing between the feed hoppers and the coextrusion head;
extrusion of the casing with cooling of the first section of the die at a temperature of about 50xc2x0 C. so as to solidify the casing;
extrusion of the stuffing which fills the casing produced in the first section with cooling of the second section of the die at a temperature of about 30xc2x0 C., the product coming out of the die having a temperature of about 38xc2x0 C.
The following are defined:
TE=temperature of the casing in the feed hopper of the system
TFn=temperature of the stuffing n in its feed hopper
TFIL 1=average temperature of the wall of the die corresponding to the length
L1
TFILn=average temperature of the wall of the die corresponding to the length
Ln-(L nxe2x88x921)
TP1=average temperature of the product at the outlet of the hollow needle 1
TPn=average temperature of the product at the outlet of the hollow needle n
TFILFIN=average temperature of the wall of the die corresponding to the length L-Ln
TPFIN=average temperature of the product at the outlet of the die.
According to one embodiment, the temperatures in the coextrusion device follow the law:
TE=TFn=TFIL1=TFILn=TFLFIN=TP1=TPn=TPFIN=2-10xc2x0 C.
According to another embodiment, for a xe2x80x9chotxe2x80x9d process, with the casing and the stuffing(s) being introduced between 30 and 80xc2x0 C., the temperatures in the coextrusion device follow the law:
TE=TFn=30-80xc2x0 C.; 80xc2x0 C. greater than TFIL 1 greater than TFIL n greater than TFILFIN=30xc2x0 C.; TP1=TPn=TPFIN=70 at 35xc2x0 C.
According to another embodiment, in a xe2x80x9chigh temperaturexe2x80x9d process, with the casing and the stuffing(s) being introduced between 90 and 100xc2x0 C., the temperatures in the coextrusion device follow the law:
TE=TFn=90-100xc2x0 C.: 80xc2x0 C. greater than TFIL 1 greater than TFILn greater than TFILFIN=30xc2x0 C.; TP1=TPn=TPFIN=85 at 35xc2x0 C.
According to a second embodiment, the envelope is formed by heating, by thermic coagulation at a temperature of more than 50xc2x0 C. and normally between 80 and 100xc2x0 C.
In this embodiment, it is possible to use products for the casing material which are meat, egg, fish flesh or surimi composites.
According to one embodiment, the coextrusion device follows the law:
TE=Tfn=2-50xc2x0 C.; TFIL 1=TFILn=TFILFIN greater than 80-100xc2x0 C.; TP 1=TPn=TPFIN=60-80xc2x0 C. thoroughly hot.
According to another embodiment, the method includes the following stages:
a preparation of the stuffing at a temperature TFn close to 90xc2x0 C. and of the casing at a temperature TE close to 7xc2x0 C. in the feed hoppers;
cooling between the feed hoppers and the coextrusion head at a temperature of close to 75xc2x0 C. for the stuffing, and at a temperature of about 4xc2x0 C. for the casing;
reheating to temperature TFIL 1 close to 45xc2x0 C. of the first section of the die so as to reduce the casing to a fluid state;
cooling to a temperature TFILFIN close to 25xc2x0 C. of the second section of the die, the stuffing being introduced into the casing at a temperature of about 50xc2x0 C., the product at the die outlet having a temperature TP FIN of about 28xc2x0 C.
According to one embodiment, the method includes the following stages:
preparation of the stuffing and casing at a temperature of about 40xc2x0 C.;
keeping the stuffing cold at a temperature of about 40xc2x0 C. as far as the coextrusion head and at the same time reheating of the casing to a temperature of about 50xc2x0 C. between the feed hopper and the coextrusion head;
heating of the first section of the die to a temperature TFIL 1 close to 98xc2x0 C. so as to solidify the casing by means of thermic coagulation;
heating of the second section of the die, the stuffing being introduced into the casing at a temperature TP1 close to 50xc2x0 C.;
the product coming out of the extrusion die having a temperature of about 80xc2x0 C.
In the first and second embodiments for the stuffing material, composite products are normally used having a cheese, meat, egg, fish flesh, surimi, fruit or vegetable base.
Moreover, the casing material has a dry extract able to reach 60% and is typically between about 30 and 50%.
According to the method, the coextrusion head is fed by two single pumps with supercharging hoppers for the stuffing material and casing material respectively.
According to one embodiment, the transfer pumps of the hoppers are connected towards the coextruding machine directly on the coextrusion system.
According to another embodiment, the pumps are connected onto a closed intermediate system fitted with a heat exchanger so as to control the temperature of these materials immediately before they enter the coextrusion head.
According to one embodiment, the pressure and distribution of the material flow intended to form the casing are adjusted with the aid of a distribution plate inserted on the channel of the casing of the product.
According to one embodiment, several coextruded segments are assembled, possibly with a gelatinizing agent, and are then treated thermically so as to obtain a restored sliceable block.
Normally, the product at the die outlet is sliced and then conditioned continuously or discontinuously.
The linear flow speed of the product at the die outlet is typically between 5 and 10 metres/minute.
According to a second characteristic, the invention concerns a coextrusion device implementing the previously described method, the device including:
means for feeding the casing material of the product;
means for feeding the stuffing material of the product;
a coextrusion chamber with a coextrusion head prolonged by a coextrusion die;
first means for transferring the casing material into the coextrusion chamber;
second means for transferring the stuffing material to the coextrusion head without mixing the stuffing material and casing material;
the longitudinal coextrusion die including:
a first die section in which the stage occurs for shaping the solid casing, this first section being traversed by at least one hollow needle, the end of the first section being defined by the outgoing extremity of the shortest hollow needle, each hollow needle transferring a stuffing material, the material of the casing coming out of the coextrusion head being transferred between the internal wall of the die and the external wall of the hollow needle(s);
a second section from the outlet of the hollow needle or needles up to the outlet of the die in which the stuffing coming out of the hollow needle is coated by the solid casing.
The hollow needles are concentric, the most peripheral one being the shortest, or non-concentric.
The length L1 of the shortest hollow needle is at least 10 cm so that the casing solidifies and normally between 30 and 150 cm, the difference between the length L of the die and the length Ln of the longest hollow needle being at least 10 cm and typically between 30 and 600 cm.
The device includes means for regulating the temperature of the first transfer means, means for regulating the temperature of the second transfer means, means for regulating the temperature of the first section of the die, and means for regulating the temperature of the second section of the die.
The die typically has a circular, parallelepiped or ludic section.
The cross section of the die is identical to or different from that of the hollow needle(s). The diameter of the cross section of the die is between 5 and 50 mm and preferably between 7 and 20 mm. Normally, the section of the die is between 1.2 and is 5 times the section of the hollow needle.
According to a third characteristic, the invention concerns a food product of the stuffed food speciality type obtained by implementing the method described previously, the product including a solid casing extending longitudinally and coating at least one stuffing, the dimension of the cross section of the product being less than 20 mm and normally between 10 and 20 mm.
Its cross section is parallelepiped, rounded or ludic.
After slicing, its length is normally between one and ten times the width of its cross section.
The stuffing may have a cheese or non-cheese composition selected from the group including butcher pastries, fish-based pastries or other sea products, fruit, herbs, spices and flavours.
According to one embodiment, the product includes at least three concentric layers, the external casing having a cheese composition;
According to the invention, the product includes a solid casing with a cheese composition extending longitudinally coating at least one stuffing, the product having a cross section with a dimension of less than 20 mm and typically between 10 and 20 mm, and the casing has a dry extract of between 40 and 60%, the product thus being able to be picked up without sticking.
The food product appears in one variant in the form of a sliceable restored block obtained by assembling several products as described previously, this restored product comprising a plurality of stuffing lining channels.